import java.util.TreeSet;

public class Demo3 {
    public static void main(String[] args) {
        Thread t = new Thread(){
            @Override
            public void run() {
                while(true)
                {
                    System.out.println("hello thread");
                    try {
                        Thread.sleep(1000);
                    }catch (InterruptedException e)
                    {
                        e.printStackTrace();
                    }
                }
            }
        };

        t.start();
        while(true)
        {
            System.out.println("hello main");
            try{
                Thread.sleep(1000);
            }catch (InterruptedException e)
            {
                e.printStackTrace();
            }
        }
    }
}
